Open-Set Learning for Addressing Label Skews in One-Shot Federated Learning

26 Sept 2024 (modified: 05 Feb 2025)Submitted to ICLR 2025EveryoneRevisionsBibTeXCC BY 4.0
Keywords: federated learning, open-set learning
TL;DR: We study the theory and experiments on open-set learning for label skews in one-shot federated ensemble.
Abstract: Federated learning (FL) is crucial for collaborative model training, yet it faces significant challenges from data heterogeneity, particularly label skews across clients, where some classes may be underrepresented or absent entirely. In one-shot FL, where clients only communicate with the server once, this problem becomes even more challenging. Recent solutions propose incorporating open-set learning (OSL) to tackle this issue by detecting unknown samples during inference, but current methods like FedOV lack adaptability to varying client data distributions. In this paper, we provide a theoretical analysis proving that improving OSL algorithms can effectively address label skews in one-shot FL, since one-shot FL is learnable through good OSL algorithms regardless of label skews. We also empirically evaluate state-of-the-art OSL algorithms and identify their limitations. Based on these insights, we propose FedAdav, an adaptive algorithm that combines OSL signals to significantly improve ensemble accuracy in one-shot FL under label skews. Through extensive experiments, we demonstrate that exploring better OSL is key to overcoming label skew challenges in federated learning.
Supplementary Material: zip
Primary Area: unsupervised, self-supervised, semi-supervised, and supervised representation learning
Code Of Ethics: I acknowledge that I and all co-authors of this work have read and commit to adhering to the ICLR Code of Ethics.
Submission Guidelines: I certify that this submission complies with the submission instructions as described on https://iclr.cc/Conferences/2025/AuthorGuide.
Anonymous Url: I certify that there is no URL (e.g., github page) that could be used to find authors’ identity.
No Acknowledgement Section: I certify that there is no acknowledgement section in this submission for double blind review.
Submission Number: 5795
Loading

OpenReview is a long-term project to advance science through improved peer review with legal nonprofit status. We gratefully acknowledge the support of the OpenReview Sponsors. © 2025 OpenReview